The world's fastest railway in areas with extremely low temperatures, which runs through three provinces in northeastern China, started operation on Saturday as part of the country's efforts to revitalize this old industrial base.

Four trains departed from stations in Harbin, capital of Heilongjiang; Changchun, capital of Jilin; Shenyang, capital of Liaoning; and Dalian, the port city in Liaoning, simultaneously at 9 a.m. on Saturday to mark the opening of the 921-km line.

The high-speed railway with designed speeds of up to 350 km per hour went into service after passing a two-month test during which the region saw blizzards and temperatures as low as minus 40 degrees Celsius.

"The operation of the Harbin-Dalian high-speed railway signals great progress in the building of a high-speed rail network with four lines running vertically up the country and four lines running horizontally across the country," said Lu Chunfang, vice minister of railways.

So far, China has 8,600 km of operating high-speed railway, more than any other nation.